European Commission Approves Viread® for HIV-1 Infection in Children and Adolescents and for Chronic Hepatitis B in Adolescents

Gilead Sciences, Inc. (Nasdaq: GILD) today announced that the European
Commission has granted marketing authorization for two new indications
for once-daily Viread® (tenofovir disoproxil fumarate). The
first new indication permits the use of Viread in combination with other
antiretroviral agents for the treatment of HIV-1 infected pediatric
patients aged 2 to less than 18 years with nucleoside reverse
transcriptase inhibitor (NRTI) resistance or toxicities precluding the
use of first line pediatric agents. Additionally, Viread is now approved
for the treatment of chronic hepatitis B virus (HBV) infection in
adolescent patients aged 12 to less than 18 years with compensated liver
disease and evidence of immune active disease. Today’s authorization
covers all 27 countries of the European Union (EU). Viread was approved
for use in combination with other antiretroviral agents as a treatment
for HIV-1 infection in adults and for chronic HBV in 2002 and 2008,
respectively, and is the most-prescribed molecule for these diseases in
major European countries.

Today’s decision includes marketing authorization for a new oral granule
formulation of Viread for HIV-1 infected children aged 2 to less than 6
years, and for HIV-1 infected children above 6 years of age for whom a
solid dosage form is not appropriate. The agency also approved three new
reduced-strength Viread tablets in doses of 123 mg, 163 mg and 204 mg
for HIV-1 infected children aged 6 to less than 12 years. The use of the
lower-strength tablets and the oral granule formulation are based on the
patient’s age and weight.

The existing, full-strength 245 mg Viread tablet formulation is now
available for use by adolescents aged 12 to less than 18 years to treat
both HIV-1 infection and chronic HBV infection in those with compensated
liver disease. For adolescents and adults for whom the 245 mg tablets
are not appropriate, the oral granule formulation may be used.

“We are pleased to provide new therapeutic options for younger patients
living with HIV and chronic hepatitis B and will work to make these
pediatric formulations available as quickly as possible,” said Norbert
Bischofberger, PhD, Executive Vice President, Research and Development
and Chief Scientific Officer, Gilead Sciences.

The new indications are supported by clinical data from three studies
examining the use of Viread among children and adolescents with HIV and
among adolescents with chronic HBV. The safety and efficacy of Viread
has not been established in children less than 2 years of age for HIV
treatment, or in children less than 12 years of age for the treatment of
chronic HBV.

In an effort to accelerate the availability of pediatric formulations in
low-income countries, where the majority of children with HIV live,
Gilead has established incentives to encourage its Indian generic
manufacturing partners to develop pediatric formulations of its HIV
treatments. Through these partnerships, Gilead already makes Viread
available at significantly reduced cost for adults living with HIV and
chronic HBV in low-income countries.

EU Important Safety Product Information About
Viread, Including Boxed Warnings

Lactic acidosis, usually associated with hepatic steatosis, has been
reported with the use of nucleoside analogues, including tenofovir
disoproxil fumarate. Lactic acidosis has a high mortality and patients
at increased risk should be followed closely.

A multidisciplinary approach is recommended for the management of
children and adolescents to weigh on a case-by-case basis the
benefit-risk balance of treatment.

Rare events of renal failure, renal impairment, elevated creatinine,
hypophosphataemia and proximal tubulopathy (including Fanconi
syndrome) have been reported with the use of tenofovir disoproxil
fumarate.

It is recommended that creatinine clearance is calculated in all adult
patients prior to initiation therapy with Viread and renal function
(creatinine clearance and serum phosphate) is also monitored every
four weeks during the first year and the very three months. In
patients at risk for renal impairment, more frequent monitoring should
be considered. In children and adolescents, renal function (creatinine
clearance and serum phosphate) should be evaluated prior to treatment
and monitored during treatment as in adults.

If renal abnormalities are detected or suspected in children and
adolescents, consultation with a nephrologist should be obtained to
consider interruption of Viread treatment.

Use of Viread should be avoided with concurrent or recent use of
nephrotoxic medications. If concomitant use of Viread and nephrotoxic
agents is unavoidable, renal function must be monitored weekly.

Viread is not recommended in adult patients with severe renal
impairment (creatinine clearance < 30 mL/min). If no alternative
treatment is available, prolonged dose intervals may be used.

Viread is not recommended for use in children and adolescents with
renal impairment.

Bone abnormalities (infrequently leading to fractures) may be
associated with proximal renal tubulopathy and appropriate
consultation should be obtained if suspected.

Viread may cause a reduction in bone mineral density (BMD) and the
effects of Viread associated changes in BMD on long term bone health
and future fracture risk are currently unknown in children and
adolescents. If bone abnormalities are detected or suspected in
children and adolescents, consultation with an endocrinologist and /or
nephrologist should be obtained.

Immune reconstitution syndrome has been reported in patients treated
with combination therapy, including Viread.

Redistribution and/or accumulation of body fat have been observed in
patients taking anti-HIV medicines. The cause and long-term effect of
these conditions are unknown.

About Gilead Sciences

Gilead Sciences is a biopharmaceutical company that discovers, develops
and commercializes innovative therapeutics in areas of unmet medical
need. The company’s mission is to advance the care of patients suffering
from life-threatening diseases worldwide. Headquartered in Foster City,
California, Gilead has operations in North America, Europe and Asia
Pacific.

Forward-Looking Statement

This press release includes forward-looking statements, within the
meaning of the Private Securities Litigation Reform Act of 1995, that
are subject to risks, uncertainties and other factors, including the
risk that healthcare providers may not see advantages of Viread for
HIV-infected children and HBV-infected adolescents over other
formulations and may therefore be reluctant to prescribe the product.
These risks, uncertainties and other factors could cause actual results
to differ materially from those referred to in the forward-looking
statements. The reader is cautioned not to rely on these forward-looking
statements. These and other risks are described in detail in Gilead's
Quarterly Report on Form 10-Q for the quarter ended September 30, 2012,
as filed with the U.S. Securities and Exchange Commission. All
forward-looking statements are based on information currently available
to Gilead, and Gilead assumes no obligation to update any such
forward-looking statements.

For more information on Gilead Sciences, please visit the company’s
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at 1-800-GILEAD-5 or 1-650-574-3000.